Means for cooling the pistons of internal-combustion engines.



B. KR'A'MER.

MEANS FOR COOLING THE PISTONS OF INTERNAL COMBUSTION ENGINES.

APPLICATION HLED Aue.26. 1914.

1,251,387. Patented Dec. 25,1917.

\Afltnesses'z Inventor:

UNITED STATES PATENT QEFIfiE.

BmNHABD KRAMER, OF CHARZOTTENBURG, GERMANY, ASSIGNOB T GENERAL ELECTRIC COMPANY, A CORPORATION OF NEW YORK.

Specification of Letters Patent.

Patented Dec. 25, 1917.

Applicaton filed August 26, 1914. Serial No. 858,632.

To all whom it may concern:

Be it known that I, BERNHARD KRAMER, a subject of the Emperor of Germany, residing at Charlottenburg, Germany, have invented certain new and useful Improvements in Means for Cooling the Pistons of Internal-Combustion Engines, of which the following is a specification.

The present invention relates to internalcombustion engines and particularly to the cooling of the piston heads.

In connection with internal combustion engines, especially those operating with crude oil on the high compression cycle, it is necessary when the pistons are relatively large in diameter to provide a coolin means for the piston heads, and to this on it has been the practice to provide the piston with a hollow head through which a suitable cooling medium is forced. In order to obtain eiiicient cooling it has been found that the cooling medium must be circulated under considerable pressure and this has resulted in considerable leakage taking place around the connection between the stationary pipes and those moving with the piston. This leakage is objectionable and particularly so where it is to the crank case as, where water, for example, is used for the cooling medium, it forms a frothy mixture with the lubricant and destroys its efiiciency.

The object of the present invention is to provide an improved means for circulating the cooling medium and comprises essentially the effecting of the circulation by means of suction instead of pressure as heretofore used. By this arrangement it will be seen that the pressure within the circulating pipes will be substantially equal to or somewhat below atmospheric so that any leakage will be in the nature of air to the pipes rather than cooling fluid therefrom.

In carrying out my invention the piston is provided with a chamber in its head with which connects suitable pipes for conveying the cooling fluid. It is necessary to arrange these pipes so as to permit of the movement of the piston and to this end the pipe sections may be suitably jointed so as to permit of an oscillatory movement, or they may be arranged to telescope, as found desirable. The pipe or pipes which convey the cooling fluid to the piston head communicate with a suitable supply of cooling fluid and the pipe or pipes which convey it away therefrom lead to the suction side of a Suitable pump, which may be of any approved type as a rotary pump, or a plunger pump. The delivery side of the pump may discharge the fluid back to the original source or not as found desirable. If it discharges back to the original source, a suitable cooling device will preferably be used.

In the drawing the single figure shows one embodiment of my invention.

Referring to the drawing, 2 indicates the cylinder and 3 the piston of an internalcombustion engine. The piston head is provided with a chamber 4 through which the cooling fluid is to be circulated. 5 is a reservoir 'or other suitable source of supply into which dips the end of the pipe 6 which connects with a stationary upright pipe 7.

8 is a pipe carried by and moving with the piston and communicating with the chamer 4. The pipe 8 surrounds and telescopes with the stationary pipe 7. 9 is a discharge pipe which is carried by the piston and telescopes with the fixed pipe 10. The lower end of the pipe 10 is connected by pipe 11 to the suction side of the pump 12, the suction valve being diagrammatically indicated at 13. 14 is the cvlinder of the pump, and 15 the piston. This pump may be operated from the engine shaft or otherwise. The telescoping pipes 7, 8 and 9, 10 make a fairly close fit so that there is little clearance between them and if desired a suitable packing may be used between them as indicated at 16. This prevents the entrance of any appreciable amount of air. In the case of the pipes 7 and 8 it is possible that particles of fluid may cling to the pipe 8 and by the movement of the piston eventually work down and leak out between the lower end of the pipe 8 and pipe 7. I accordingly provide a small trap or receptacle 17 which surrounds the lower ends of these pipes, and connected therewith is a suitable drain pipe 18.

The delivery side of the pump is shown as being connected by pipe 19 to the reservoir 5, 20 indicates the delivery valve.

The operation of the apparatus shown will be obvious, the pump on the suction stroke drawing fluid from the tank 5 up through the pipes 6, 7 and 8 to the chamber 4 and from there through pipes 9, 10 and 11 to the pump cylinder, and on the discharge stroke forcing the fluid from. the pump cylinder back to the tank 5. Owing to the arrangement of the pipe 19 and tank 5 any air entrained with the cooling fluid will have an opportunity to escape and hence be prevented from entering the pipe 6. i

In accordance with the provisions of the patent statutes, I have described the principle of operation of my invention, together with the apparatus which I now consider to re resent the best embodiment thereof; but I esire to have it understood that the apparatus shown is only illustrative, and that the invention can be carried out by other means. j

What I claim as new and desire to secure by Letters Patent of the United States, is,

1. The combination in an internal combustion engine, of a piston having a chamber in its head, relatively movable conduits leading to and from said chamber, and pump means-to the suction side of which the conduits leading from the chamber are connected, for sucking a cooling fluid through the conduits and the chamber.

2. The combination in an internal-combustion engine, of a piston having a chamber in its head, a source of cooling fluid, a pump, and relatively movable pipes connecting the chamber with the source and with the tion side of the pump.

3. .The combination in an .internal-com-;

bustion engine, of a piston having a, cham .ber in its head, a source of cooling fluid, a pump, relatively movable pipes connecting the chamber with the source and with the suc-.

- handthis 21st day of July, 1914..

nee-nee"? suction side of the pump, and a pipe for conveying the fluid from the delivery side of the pump back to the source.

4:- The combination in an internal 'com bustion engine, of a piston having a chamber in its head, pipes connected to said piston and communlcating with the chamber, said pipes being adapted to move relative to each other, a source of cooling fluid, and a pum having its suction side connected to sai pipes for sucking cooling fluid through the chamber in the head.

5. The combination in an internal combustion engine, of a piston having a chamber in its head, a source of cooling fluid, a pump, telescoping pipes connecting the source with the chamber, and telescoping pipes connecting the chamber to the'suction side of the pump. 7 I

6. The combination in an internal-combustion engine, of a piston having a chamber in its head, a source of cooling fluid, a pump, telescoping pipes connecting the source with the chamber, a wall forming a trap around the lower end or" the pipes,a drain pipe lead mg from the trap, and telescoping pipes con- I necting the chamber to the suction side of the pump.

In Witness whereofil have hereuntoset my BERNHARD Witnesses:

Dncnamrs, F. U. BRANN. 

